This is a handheld Acoustic Tractor Beam which can levitate small light objects like Styrofoam balls. It is based on the design made by Asier Marzo, to which I made a 3D-printable enclosure and change some of the electrical components, all this to make it a bit more integrated and usable friendly. The material and components for the original project and instructions on how to build it can be found at: http://www.instructables.com/id/Acoustic-Tractor-Beam/
The CAD file for Rhino (.3dm) is also provided so that you can modify the enclosure as you like.
Feel free to post you prints!
Holes for cables and such are not made in the design, since this was a one-of pioneer build, and so also mounting hole to fix the battery holder. Furthermore, the bottom of the bowl from the original project needs to be removed to make room for the driver. This part of the bowl is not of concern because no transducers are needed there anyhow. Chamfering the top edge of the bowl is also a good idea.
The difference in material as appose to the original design are as follow. I used a 3,7V Li-ion battery, of type 18650, with holder and a USB-changing/step-up circuit to supply the l Arduino Mini Pro and "L298N" Dual Motor Driver with 5VDC. The main power switch is a regular single pole type and it is connected after the battery's charge/step-up circuit. After that I use an other step-up circuit to drive the transducers via the motor driver and this output is controlled by the potentiometer on the front side from ~15VDC to ~25VDC. All these components are fixed easily in the empty part of the handle.
The joystick (above the power switch) is used to control the hight of the sonic trap and it is taken from an old Volvo car (700/900 series) where it was used for the power mirrors.
Some modifications are needed for the components to fit inside the enclosure, like de-soldering all the PCB terminal blocks of the driver, adding just the wires. Also filling down the sides of the heat sink and edges of the PCB is necessary for it to fit.
This is my original drawing with inspiration taken from real pistol grips. The design is made to be strong and printer friendly, but requires some support for the bridges and steep slopes.